Wire stripping tool



H. W. NORMAN El AL July 17, 1951 WIRE STRIPPING T001.

2 sheets-sheet 1 Filed Sept. 11, 1947 FIG.

FIG. 2

//v|//v TORS HW NORMAN ,1 N R01. L lNGS A T TORNE Y July 17, 1951 H. w. NORMAN I EIAL WIRE STRIPPING TOOL '2 Sheets-Sheet 2 Filed Sept. 11, 1947 FIG. 4

UV l/E N TORS haw NORMAN. JN ROL u/vas FIG. 5

- A r TORNE I Patented July 17, 1951 WIRE STRIPPING TOOL Hollis W. Norman and James N. Rollings, Baltimore, Md., assignors to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application September 11, 1947, Serial No. 773,376

2 Claims.

This invention relates to stripping tools, and more particularly to a tool for stripping the textile covering from the end of cords used in communications apparatus.

In general, the various types of cords used in connection with communications apparatus comprise a plurality of conductors twisted together and covered by suitable textile covering which has been applied by conventional knitting or braiding operations. In the manufacture of such cords it is necessary to remove the textile covering from the end of the cord so that terminal lugs can be clamped on the ends of the individual conductors by suitable automatic machines. In the past the operator of the terminal clamping machine removed the portion of the textile covering by means of scissors. This method of removing the textile covering proved to be costly, timeconsuming and very tiring on the operator.

An object of the invention is to provide new and improved tools for stripping textile coverings from cords.

A tool for stripping the textile covering from the ends of cords embodying certain features of the invention comprises a round-nosed nib for piercing the textile covering at the starting point of the stripping operation, a knife blade positioned against the opposite side of the nib having its cutting edge slightly back of and below the nib for slitting the covering as the end thereof is drawn across the nib, and means spacedly positioned with respect to the piercing means and associated knife edge for directing the end of the cord along a predetermined path with respect to the nib and associated slitting knife.

A complete understanding of the invention will be had from the following detailed description of a specific embodiment thereof, when read in conjunction with the appended drawings, in which:

Fig. 1 is an isometric view of a braid stripping tool embodying specific features of the invention;

Fig. 2 is an exploded view showing each component of the tool, shown in Fig. l in its proper position with respect to the associated parts of the tool;

Fig. 3 is an enlarged, front elevation of the tool showing a cord positioned on the tool with the braid thereof engaged by the knife of the tool;

Fig. 4 is an enlarged, sectional view taken along line 44 of Fig. 3, and

Fig. 5 is an enlarged, sectional view taken along line 55 of Fig. 4.

Referring now to the drawings, and more particularly to Figs. 1 and 2, a rectangular base [0 is provided with a thin flange l l extending along the top and right hand side thereof and forming an elongated shoulder [2 at its junction with the base. The base Ill is provided with a recessed portion l3 which is designed to receive a retainer Hi, the depth of the recess 13 being substantially less than the thickness of the retainer. The retainer M is provided with a groove [5 in which a thin knife blade Hi and a relatively thin pilot member ll are positioned in the order named. The retainer I4, having the blade l6 and the pilot member ll assembled in the groove I5, is positioned in the recess l3 of the base H), in which position the retainer it serves to hold the blade l6 and the pilot member I! against the surface of the recess [3. A plate 20 is provided with a recessed portion 2| and is arranged to be positioned on the base Ii} so that the recess portion 2| engages the portion of the retainer l4 extending beyond the recess I3 of the base I0. A pair of dowel pins 2222 serve to properly align the clamping plate 20 with respect to the base l0 and a screw 23 is arranged to threadedly engage a tapped bore provided in the base It] and thereby clamp the plate 20 tightly on the base Ill. The above-described parts are assembled in this manner to form the composite stripping tool shown in Fig. l.

The pilot member I7 is provided with a vertical ear 24 having a round-nosed nib 25 formed on the right side thereof and extending substantially to the right of the front edge of the pilot member IT. The blade I6 is provided with a short, armate-shaped knife edge 25 on the upper end thereof, the extreme top edge of which is arranged to butt against a Shoulder 2! formed at the base of the nib 25. The retainer I4 is provided with an ear 28 of substantially the configuration as the ear 24 which causes the nib 25 of the pilot member ll, in which case, the upper end of the ear 28 also engages the shoulder 2'! at the base of the nib 25. The ears 24 and 28 are shaped to expose only a desired portion of the cutting edge of the knife 26 from the under side of the nib to the top edge of the retainer 14. The base of the arcuate-shaped knife edge 26 extends beyond the front edge of the blade 16 to form a shoulder 29 which abuts the top edge of the retainer when it is assembled therein and serves to hold the knife edge in position with respect to the nib 25. The retainer l4 and the pilot member l! are assembled in the tool so that the bottomedges thereof are flush with the bottom of the base [0 and the plate 20, which arrangement locates the nib 25 with respect to the shoulder l2 of the base ID. The right hand corner of the flange I l is highly polished and a portion of the right hand corner of the shoulder I2 adjacent to the nib 2'5 is rounded and polished, which two surfaces serve to guide a cord as it is drawn across the nib 25 in a manner to be hereinafter described. I

Referring 'nowto Figs. 3 and 4; it will'beno'ted that the end of a cord indicated generally at 30 is shown in the slitting position on the tool, that is, after the nib 25 has pierced and entered inside a textile covering 3 I, enclosing a plurality of conductors 3232 spirally twisted together to form the core of the cord'3fi. In this position, the cord Sil is squeezed in between the flange ii and the car 24 which carries the nib 25, and the bottom of the periphery of the cord is resting on the shoulder :2, as shown in Fig. 5. "When the nib enters inside the covering 3|, the-under side thereof engages the inside of the covering and tends to hold the cord downon theshoulder l2 and in'betw'een the flange 'H and" the nib 25. T'hefiange H is spaced from 'thenib 25' so that when the cord Sal is placed onthefiange ll the nib will pierce the covering'3l. at a point substantially tangent to the core formed. by the twisted conductors iii-32 (Fig. 5). The'sh'oulder i2 is located with respecttothe nib 25 to prevent the nib from engaging the inside of or projecting through the portion ofthe covering 3! disposed directly above the portion pierced by the nib, thereby acting to keep the nib inside the covering. The position of the nib 25 with respect to 1e flange 1 i and the shoulder 12 is critical with respect to the operation of the tool and is determined in each case from the diameter of the cord from which the textile covering is to be clamp-ed between the car 24 which carries the nib iffiand the ear 2% of theretainer i l-in the manner hereinbefore described, it cannot touch the conductors 3232 '(Fig. 5) as the nib :passes through the covering. A stay band 33 hasbeen attached on the cord 39 a predetermined distance from the right hand end thereof, and it is necessary to removethat portion of the covering 3i which extends from the edge of the stay band 33 to the right end of the cord in order that suitable te individual conductors 32 32.

The above-described tool operates in the following manner to strip the textile covering from the end of a cord:

Let it be assumed that the composite toolis positioned on a suitable work table in such a manner that the end of a cord; such as theJcord 39 may be drawn easily across the -nib 25 and the knife edge 26 of the tool in a direction indicated in Fig. 3. The end of the cord is first placed on the flange H of the base at a'relatively sharp angle so that the covering 3! is against the end or" the nib'at a point directly to the right of the stay band 33. Having placed the cord in this position on the flange and the nib,- the cord is urged slightly against the nib and at the same time drawn tothe left; which movement immediately causes the nib 25 to catch in the interstices and pierce the covering 3'! ate, point adjacent to the stay band 33; 'The' nib-passes-into r inals may be clamped on the ends of the the covering 31 until the periphery of the cord 33 rests on the rounded and polished portion of the shoulder l2, whereupon the cord 38 is now squeezed in between the flange H and the ear 24 which carries the nib 25. Due to the position of the nib with respect to the flange, the nib enters thecovering at a point substantially tangent 'to theoonductor core Qfallhfi cord" 3,0;as viewed in Fig. 3. The nib is positioned above the rounded corner of the shoulder l2 a distance which will permit the nib to enter a sufficient distance inside the covering, but will prevent the nib from coming out of the portion of the covering directly above the nib. After the nib 25 has pierced the covering 31, the cord 33 is then drawn across the nib in adirection substantially parallel to the longitudinal axis of the base ID or at a slight angle thereto, whichmovement directs the coveringfdirectly behind the nib against the knife edge 26 which slits the covering. During the slitting -=0peration of the covering the fiat sideof the nib .doing,'all of the main threadsof the braidedoovering are cut in a very short strokeiof the-cord so that a substantial-portion of the end of thebraided covering is removed from theend of the cord as a braided tube. -However, when the covering 31 is braided tightlyon the cord or is a :knittedtype of covering, it is necessary to draw the cord 39 to the left until the entire end of the covering is slit from the stay band 33 to the end of the cord.

While the above-described tool-is particularly well adaptedtoremove.textilecoverings from the ends of-cords used in connection with communications apparatus, it may be readily adaptedto strip varioustypes of coveringsfroin the ends of conductors and cables without departing from -the:spirit and scope of therinvention. set. forth in the. appended K claims.

2What is claimed is:

1-; A; tool'for stripping the textile covering enclosing'the conductorcore of cords, which -cornprises a body member, a painof guiding suriaces formed on the body member at right angles to eachotherfor-directing theend of a cord along a predetermined path-as it is drawn across *the tool to slit the textile coveringthereof, a

plate having a round-nosednib supported from one corner thereof positioned against the body rnember, saidnib being positioned withrespect to" the guiding surfaces so that when the end of a cord is-drawn against the nib it pierces the of the cordandis prevented from projecting out of thec'overing; immediately above its'point of entrance, a knife blade positioned against the plate and having its cutting edge projecting from onecorner' thereof slightly behind and below the nib of said plate, a retainerfor holding the plate and the blade inposition with respect to: said body member, said blade having a' shoulder provided at the base of: the: cutting .edge". therefor ior= locatingthei cutting. edge with respect tosthe nib, and means for clamping the retainer in place against the body member.

2. A tool for stripping a braided covering enclosing the conductors of a cord, which comprises a rectangular base having guide surfaces extending along one edge thereof over which a portion of a cord may be advanced and having a recess in one face thereof, a plate having a round-nosed nib projecting from one corner at right angles to one edge thereof positioned in said recess of the base so that the nib is spaced a predetermined distance from one of the guide surfaces of the base so that the nib will pierce the braided covering as the cord is drawn across the guide surfaces, a blade positioned against the plate and having a knife edge projecting beyond and along a portion of one edge thereof, said knife edge serving to slit the braided covering as the end of the cord is drawn longitudinally across the guide surfaces, a retainer having a groove therein to align the nib and the knife edge so that the knife edge is slightly to the rear of the nib, said retainer having a shoulder 6 which positions the knife edge a predetermined distance below the nib and having an ear projecting therefrom so as to hold the projecting portion of the blade against the projecting portion of the plate, and means for clamping the retainer in the recess of the base so as to hold the nib and the blade a predetermined distance from the other guide surface of the base.

HOLLIS W. NORMAN.

JAMES N. ROLLINGS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,739,972 Klinger Dec. 1'7, 1929 1,866,095 Foley July 5, 1932 1,977,677 Hill Oct. 23, 1934 1,998,391 Shaw Apr. 16, 1935 2,306,403 Mortensen Dec. 29, 1942 

